(CNN) – An indigenous activist who protested against illegal logging in Mexico's Sierra Madre mountains has been killed, highlighting the dangers that Latin American environmentalists face.

Isidro Baldenegro López, 51, a leader of the Tarahumara people and fervent environmentalist -- was shot dead Sunday at his uncle's home in the town of Coloradas de la Virgen in the state of Chihuahua, according to Mexican state-run news agency Notimex.

He was shot at least six times by a gunman, who fled the scene along with the weapon, the Chihuahua prosecutor's office said.

The police have launched an operation to capture the suspect.

In 2005, Baldenegro López won the Goldman Environmental Prize for his dedication in organizing peaceful protests against illegal logging.

"He was a fearless leader and a source of inspiration to so many people fighting to protect our environment and indigenous people's rights," the Goldman Environmental Foundation said in a statement Wednesday. […]

Global Witness, an organization that seeks to expose corruption and environmental abuse, said 2015 was the deadliest year on record, citing the "killings of land and environmental defenders -- people struggling to protect their land, forests and rivers."

A report from the group documented 185 killings across 16 countries in 2015. It found this figure was more than double the number of journalists killed in the same period. [more]